diff --git a/runs/frontier-fidelity-envelope-v1/.gitignore b/runs/frontier-fidelity-envelope-v1/.gitignore
new file mode 100644
index 0000000..008f888
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/.gitignore
@@ -0,0 +1,8 @@
+__pycache__/
+a1-native-smoke/
+a2-measured-fix-smoke/
+simulator-a1/
+simulator-a2/
+simulator-a3/
+fleet-state/
+fleet-artifacts/
diff --git a/runs/frontier-fidelity-envelope-v1/experiment-card.md b/runs/frontier-fidelity-envelope-v1/experiment-card.md
new file mode 100644
index 0000000..c1563db
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/experiment-card.md
@@ -0,0 +1,76 @@
+# EXP-SIMFID-ENVELOPE-V1：Frontier best-effort fidelity envelope
+
+> **状态：** 已批准，准备执行（2026-07-17）。用户要求先把 simulator 现有能力跑到最好，并同时覆盖 fixed input/output 与真实 trace replay。
+
+## Claim 与可证伪假设
+
+- **研究问题：** 在不使用被评测 config/workload 的 serving E2E calibration 时，Frontier 的 measured operator/collective profiles 与 scheduler state abstraction，是否足以找到真机上的低-regret config？
+- **H-CC：** Qwen30 prefill-only 的 TP 排序错误主要来自默认 analytical all-reduce；注入同机、同 TP 的 measured collective 后，已知 `2048/1` surface 的 regret 降至不超过 5%，Kendall tau-b 升至至少 0.8。
+- **H-BATCH：** 若 H-CC 不足，错误主要来自 pure-prefill attention 只有 batch=1 profile，而 Frontier 在多请求 batch 上使用没有 coverage 的 `attn_prefill_mixed` 外推；增加 MBT 可达的真实 batch composition 后可恢复排序。
+- **H-STATE：** 若 measured collective 与 batch-composition profile 都不能恢复排序，则缺失量位于 isolated operators 之外的 scheduler-state-conditioned step composition；继续增加静态 kernel rows不是有效修复。
+- **成功门槛：** worst selected-config regret `<=5%`、tie-aware Kendall tau-b `>=0.8`、真机 capacity bracket 不足以反转 top decision，并且没有使用同一 surface 的 E2E scalar calibration。
+
+## Simulator ablation（先用已有 ground truth，零新增 GPU 成本）
+
+| variant | compute profile | collective | 目的 |
+|---|---|---|---|
+| A0 | vLLM 0.20 frozen profile-v2 | Frontier analytical | 已冻结 baseline |
+| A1 | 同 A0 | Frontier 原生 Vidur + measured TP2/TP4 CSV | 检查原生 profile consumption；大 payload fallback 保留并计数 |
+| A2 | 同 A0 | measured Vidur，cache miss 直接调用已训练 estimator | 最小 correctness fix；消除 `>100k elements` 静默 analytical fallback |
+| A3 | 增加 pure-prefill batch-composition rows | 同 A2 | 检验 batch-composition coverage 是否是剩余误差来源 |
+
+A1/A2/A3 都重新运行完整 `TP∈{1,2,4} × MNS∈{8,16,32,64}` surface；TP1 无 all-reduce。所有 simulator variants 在查看新增真机 case 前冻结。A2 是单独标注、带单测的 compatibility patch，不与 Frontier upstream 原生能力混写。
+
+## Workload matrix
+
+| ID | workload | arrival / prefix | phase role |
+|---|---|---|---|
+| F0 | fixed `ISL=2048, OSL=1` | uniform QPS；distinct prefixes | 已有 real ground truth，选择 A0--A3 |
+| F1 | fixed `ISL=512, OSL=1` | uniform QPS；distinct prefixes | short-prefill、多请求 batch composition |
+| F2 | fixed `ISL=2048, OSL=128` | uniform QPS；distinct prefixes | true prefill+decode mixed serving |
+| T1 | `thinking_w20260327_1000` eligible trace | 原 timestamp/order；exact prompt/output/session/hash；prefix on | production joint distribution 与 cache/scheduler feedback |
+
+T1 只排除已经审计的 72 个超 40,960 context rows 和 6 个 zero-output rows，eligible universe 为 `15,401/15,479`。负载轴只使用 trace 已有、同 session 共享的 `sampling_u`；入选 request 的 arrival、input/output、prompt、hash 和相对次序不变。真实 runtime 设置 `min_tokens=max_tokens=output_length` 且 `ignore_eos=true`，逐请求核对 usage。
+
+## 固定系统与 config surface
+
+| 项目 | 冻结设置 |
+|---|---|
+| machine | 仅 `dash0`，8×NVIDIA H20 |
+| model/runtime | `/home/admin/cpfs/wjh/models/Qwen/Qwen3-30B-A3B`；community vLLM 0.20.0+cu129；BF16 weight/activation/KV |
+| simulator | Frontier `d9cfeb6d8791fbf2f295dd9744c56a666171776e` + manifest 中列出的现有 compatibility patches；A2 patch 独立 hash |
+| configs | `TP∈{1,2,4} × MNS∈{8,16,32,64}`；DP=PP=EP=1；MBT=8192；block=16 |
+| runtime | chunked prefill on；fixed cases prefix off；T1 prefix on；fresh server per `(config, load, round)` |
+| score | `capacity(c)=max tested offered req/s with joint SLO pass rate >=0.95`；primary `capacity/actual TP GPUs` |
+| SLO | TTFT `<=1000ms + 1000×ISL/8000`；mixed case同时要求 TPOT `<=150ms`；另报告 50/100/180ms sensitivity，不用 sensitivity 改写 primary |
+
+F0 沿用已经冻结的 rate lattice与两个 fresh-server rounds。F1/F2 先由冻结 simulator 给出 boundary，再加入共同 per-GPU guard anchors，避免只测 simulator 预测附近而漏掉真实最优。每个 boundary anchor 两个 fresh-server rounds，二者都 pass 才算 feasible。
+
+T1 保持原 600 秒 arrival window。先在 simulator 上冻结 `sampling_u` bracket；真机只运行 topological guard set `{TP1,TP2,TP4} × {MNS8,MNS32,MNS64}`，若 top set 或 bracket 仍可能被未测 MNS 反转再补 MNS16。每个入选 source-row vector在 real/sim 两侧必须有相同 digest；至少两个 session-hash folds，若本轮只完成一个 window则明确标为 single-window evidence。
+
+## 诊断与停止规则
+
+1. A1 必须报告每次 collective prediction 的 measured-model hit 与 analytical fallback 次数；不能只看最终 rank。
+2. A2 对超过 100k elements 的 payload 必须由单测证明走 estimator；A2 若不改变任何 TP2/TP4 step，立即停止并检查 CLI/config 注入，不进入 GPU。
+3. A3 profile 只覆盖 MBT=8192 可达的 pure-prefill composition：F0 为 `1/2/4 × q2048`，F1 为 `1/2/4/8/16 × q512`，TP1/2/4 分别实测；不做无边界的 profile sweep。
+4. 若 A3 在 F0 仍不能达到 fidelity gate，先采集 `TP1@8, TP2@16, TP4@32` 的 per-step batch/queue/component residual；禁止用 per-TP E2E scale把答案拟合正确。
+5. 只有 best-effort simulator 在 F0 通过或形成可解释、可定位的失败后，才运行 F1/F2/T1 真机；任一 case 的结论不外推到其它 workload。
+
+## 预期成本与产物
+
+- simulator A1--A3：CPU only，约 1--3 小时总 CPU wall，0 GPU-hour。
+- attention composition profile：3 张 H20 并行，预计 5--10 分钟，`<0.5 H20-GPU-hour`。
+- F1/F2 real boundary：预计合计 12--24 H20-GPU-hours，smoke 后再锁定。
+- T1 real boundary：600 秒原 arrival window使单 anchor较贵；预计 30--60 H20-GPU-hours，必须在 simulator bracket 和一配置 smoke 后重新 echo 精确预算。
+- 产物：variant/profile manifests、full surfaces、anchor-level request metrics、rank/regret/confusion tables、profile-consumption counters，以及 fixed-vs-trace fidelity summary figure。
+
+## Benchmark design audit
+
+| 风险 | 处理 |
+|---|---|
+| selective benchmarking | 预先冻结 F0/F1/F2/T1，不因结果删除失败 case |
+| calibration=evaluation | 禁止使用同一 surface 的 serving E2E scalar；microprofile GPU 成本单独报告 |
+| trace filtering | 只做 context/zero-output correctness exclusion和 session-coherent thinning，不按长度筛选 |
+| simulator-guided real sampling | 使用共同 guard anchors；未闭合 bracket 不能宣布 top match |
+| absolute-vs-rank metric | 同时报绝对 capacity/latency、rank、regret、tau-b、pair direction和 SLO confusion |
+| hidden fallback | A1/A2 强制计数 measured-model hit/fallback，并写入 frozen manifest |
diff --git a/runs/frontier-fidelity-envelope-v1/fleet.toml b/runs/frontier-fidelity-envelope-v1/fleet.toml
new file mode 100644
index 0000000..612e4f7
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/fleet.toml
@@ -0,0 +1,24 @@
+version = 1
+
+[paths]
+state_dir = "runs/frontier-fidelity-envelope-v1/fleet-state"
+artifacts_dir = "runs/frontier-fidelity-envelope-v1/fleet-artifacts"
+
+[ssh]
+connect_timeout_sec = 10
+
+[scheduler]
+gpu_free_memory_mb = 1024
+gpu_free_utilization_pct = 10
+prefer_pack = true
+
+[sync]
+mode = "scp"
+local_path = "runs/frontier-fidelity-envelope-v1/remote-sync-marker"
+
+[[hosts]]
+name = "dash0"
+ssh_alias = "dash0"
+enabled = true
+sync_remote_path = "/home/admin/cpfs/wjh/aituner/fidelity-envelope-sync-marker"
+fleet_root = "/home/admin/cpfs/wjh/aituner/gpu-fleet-fidelity-envelope-v1"
diff --git a/runs/frontier-fidelity-envelope-v1/jobs_attention_composition.toml b/runs/frontier-fidelity-envelope-v1/jobs_attention_composition.toml
new file mode 100644
index 0000000..7e2aa3b
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/jobs_attention_composition.toml
@@ -0,0 +1,43 @@
+version = 1
+
+[[jobs]]
+name = "qwen30-attention-composition-tp1-20260717-v1"
+gpus = 1
+gpu_model = "H20"
+hosts = ["dash0"]
+command = "cd /home/admin/cpfs/wjh/aituner/aituner-qwen30-vllm020-profile-v1/runs/frontier-fidelity-envelope-v1 && timeout --signal=TERM --kill-after=30s 900 bash run_flashattn_composition.sh"
+artifacts = ["artifacts/attention-composition-tp1-v1"]
+
+[jobs.env]
+HOME = "/tmp/wjh"
+XDG_CACHE_HOME = "/tmp/wjh/.cache"
+TP = "1"
+OUTPUT_ROOT = "/home/admin/cpfs/wjh/aituner/gpu-fleet-fidelity-envelope-v1/artifacts/attention-composition-tp1-v1"
+
+[[jobs]]
+name = "qwen30-attention-composition-tp2-20260717-v1"
+gpus = 1
+gpu_model = "H20"
+hosts = ["dash0"]
+command = "cd /home/admin/cpfs/wjh/aituner/aituner-qwen30-vllm020-profile-v1/runs/frontier-fidelity-envelope-v1 && timeout --signal=TERM --kill-after=30s 900 bash run_flashattn_composition.sh"
+artifacts = ["artifacts/attention-composition-tp2-v1"]
+
+[jobs.env]
+HOME = "/tmp/wjh"
+XDG_CACHE_HOME = "/tmp/wjh/.cache"
+TP = "2"
+OUTPUT_ROOT = "/home/admin/cpfs/wjh/aituner/gpu-fleet-fidelity-envelope-v1/artifacts/attention-composition-tp2-v1"
+
+[[jobs]]
+name = "qwen30-attention-composition-tp4-20260717-v1"
+gpus = 1
+gpu_model = "H20"
+hosts = ["dash0"]
+command = "cd /home/admin/cpfs/wjh/aituner/aituner-qwen30-vllm020-profile-v1/runs/frontier-fidelity-envelope-v1 && timeout --signal=TERM --kill-after=30s 900 bash run_flashattn_composition.sh"
+artifacts = ["artifacts/attention-composition-tp4-v1"]
+
+[jobs.env]
+HOME = "/tmp/wjh"
+XDG_CACHE_HOME = "/tmp/wjh/.cache"
+TP = "4"
+OUTPUT_ROOT = "/home/admin/cpfs/wjh/aituner/gpu-fleet-fidelity-envelope-v1/artifacts/attention-composition-tp4-v1"
diff --git a/runs/frontier-fidelity-envelope-v1/materialize_frontier_allreduce.py b/runs/frontier-fidelity-envelope-v1/materialize_frontier_allreduce.py
new file mode 100644
index 0000000..bb57bc0
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/materialize_frontier_allreduce.py
@@ -0,0 +1,115 @@
+#!/usr/bin/env python3
+"""Convert frozen vLLM collective measurements to Frontier Vidur CC CSV."""
+
+from __future__ import annotations
+
+import argparse
+import csv
+import hashlib
+import json
+from pathlib import Path
+
+
+FIELDS = (
+    "time_stats.all_reduce.min",
+    "time_stats.all_reduce.max",
+    "time_stats.all_reduce.mean",
+    "time_stats.all_reduce.median",
+    "time_stats.all_reduce.std",
+    "rank",
+    "num_workers",
+    "size",
+    "collective",
+    "devices_per_node",
+    "max_devices_per_node",
+)
+
+
+def sha256(path: Path) -> str:
+    digest = hashlib.sha256()
+    with path.open("rb") as source:
+        for chunk in iter(lambda: source.read(1 << 20), b""):
+            digest.update(chunk)
+    return digest.hexdigest()
+
+
+def convert(input_path: Path, output_path: Path) -> dict[str, object]:
+    payload = json.loads(input_path.read_text())
+    if payload.get("schema_version") != "qwen30_vllm020_allreduce_frozen.v1":
+        raise ValueError(f"unexpected input schema: {payload.get('schema_version')!r}")
+
+    rows = []
+    seen = set()
+    for source in payload["rows"]:
+        tp = int(source["tensor_parallel_size"])
+        tokens = int(source["num_tokens"])
+        key = (tp, tokens)
+        if key in seen:
+            raise ValueError(f"duplicate collective row: {key}")
+        seen.add(key)
+        if tp not in (2, 4):
+            raise ValueError(f"unsupported TP: {tp}")
+        expected_bytes = tokens * int(source["hidden_dim"]) * 2
+        if int(source["payload_bytes"]) != expected_bytes:
+            raise ValueError(f"payload mismatch for {key}")
+
+        # Frontier Vidur consumes only the median target. The raw profiler kept
+        # per-rank distributions but not aligned per-repeat critical-path
+        # samples, so do not invent critical-path min/mean/max/std. Repeating
+        # the observed critical-path median in the unused fields keeps the CSV
+        # schema explicit without changing the trained target.
+        median = float(source["critical_path_median_ms"])
+        rows.append(
+            {
+                "time_stats.all_reduce.min": median,
+                "time_stats.all_reduce.max": median,
+                "time_stats.all_reduce.mean": median,
+                "time_stats.all_reduce.median": median,
+                "time_stats.all_reduce.std": 0.0,
+                "rank": 0,
+                "num_workers": tp,
+                "size": expected_bytes,
+                "collective": "all_reduce",
+                "devices_per_node": tp,
+                "max_devices_per_node": 8,
+            }
+        )
+
+    expected = {(tp, tokens) for tp in (2, 4) for tokens in (1, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192)}
+    if seen != expected:
+        raise ValueError(f"collective coverage mismatch: missing={expected - seen}, extra={seen - expected}")
+
+    output_path.parent.mkdir(parents=True, exist_ok=True)
+    with output_path.open("w", newline="") as output:
+        writer = csv.DictWriter(output, fieldnames=FIELDS, lineterminator="\n")
+        writer.writeheader()
+        writer.writerows(sorted(rows, key=lambda row: (row["num_workers"], row["size"])))
+
+    return {
+        "schema": "frontier-vidur-allreduce-materialization-v1",
+        "source": str(input_path.resolve()),
+        "source_sha256": sha256(input_path),
+        "output": str(output_path.resolve()),
+        "output_sha256": sha256(output_path),
+        "rows": len(rows),
+        "tp_coverage": [2, 4],
+        "target": "time_stats.all_reduce.median",
+        "unused_stat_policy": "repeat critical_path_median; std=0",
+        "payload_contract": "size=num_tokens*hidden_dim*2_bytes",
+    }
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--input", type=Path, required=True)
+    parser.add_argument("--output", type=Path, required=True)
+    parser.add_argument("--manifest", type=Path, required=True)
+    args = parser.parse_args()
+    manifest = convert(args.input, args.output)
+    args.manifest.parent.mkdir(parents=True, exist_ok=True)
+    args.manifest.write_text(json.dumps(manifest, indent=2, sort_keys=True) + "\n")
+    print(json.dumps(manifest, sort_keys=True))
+
+
+if __name__ == "__main__":
+    main()
diff --git a/runs/frontier-fidelity-envelope-v1/mock-fidelity-envelope.png b/runs/frontier-fidelity-envelope-v1/mock-fidelity-envelope.png
new file mode 100644
index 0000000..0e63a4e
Binary files /dev/null and b/runs/frontier-fidelity-envelope-v1/mock-fidelity-envelope.png differ
diff --git a/runs/frontier-fidelity-envelope-v1/patches/0001-vidur-large-payload-model-prediction.patch b/runs/frontier-fidelity-envelope-v1/patches/0001-vidur-large-payload-model-prediction.patch
new file mode 100644
index 0000000..56eac1f
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/patches/0001-vidur-large-payload-model-prediction.patch
@@ -0,0 +1,84 @@
+diff --git a/frontier/cc_backend/backends/vidur_cc_backend.py b/frontier/cc_backend/backends/vidur_cc_backend.py
+index ca1983a..0c57f05 100644
+--- a/frontier/cc_backend/backends/vidur_cc_backend.py
++++ b/frontier/cc_backend/backends/vidur_cc_backend.py
+@@ -882,2 +882,21 @@ class VidurCCBackend(BaseCCBackend):
+-        # Fallback to analytical if not in cache
+-        logger.debug(f"num_tokens={num_tokens} not in cache, using analytical fallback")
++        # The precomputed lookup is capped at 100k elements, while realistic
++        # TP payloads are commonly much larger. A cache miss does not mean the
++        # measured-data model is unavailable: predict on demand and memoize the
++        # exact payload instead of silently switching model families.
++        with self._cache_lock:
++            model = self._models.get("all_reduce")
++        if model is not None:
++            features = pd.DataFrame({"num_tokens": [num_tokens]})
++            result = float(model.predict(features)[0])
++            with self._cache_lock:
++                self._predictions["all_reduce"][(num_tokens,)] = result
++            logger.debug(
++                f"predict_allreduce: data_size={data_size_bytes}, num_tokens={num_tokens}, "
++                f"result={result:.6f} ms (ML model, on-demand cache miss)"
++            )
++            return max(0.0, result)
++
++        logger.debug(
++            f"num_tokens={num_tokens} not in cache and model unavailable, "
++            "using analytical fallback"
++        )
+diff --git a/tests/unit/test_vidur_cc_large_payload.py b/tests/unit/test_vidur_cc_large_payload.py
+new file mode 100644
+index 0000000..7e87aa7
+--- /dev/null
++++ b/tests/unit/test_vidur_cc_large_payload.py
+@@ -0,0 +1,50 @@
++from __future__ import annotations
++
++import threading
++import unittest
++
++import numpy as np
++
++from frontier.cc_backend.backends.vidur_cc_backend import VidurCCBackend
++
++
++class RecordingModel:
++    def __init__(self, value: float) -> None:
++        self.value = value
++        self.features = []
++
++    def predict(self, features):
++        self.features.append(features.copy())
++        return np.array([self.value])
++
++
++class VidurCCLargePayloadTest(unittest.TestCase):
++    def test_cache_miss_uses_measured_model_and_memoizes(self) -> None:
++        backend = object.__new__(VidurCCBackend)
++        backend._cache_lock = threading.RLock()
++        backend._num_devices = 2
++        backend._predictions = {"all_reduce": {(100000,): 0.1}}
++        model = RecordingModel(0.321)
++        backend._models = {"all_reduce": model}
++        backend._analytical_fallback_allreduce = lambda *_: self.fail(
++            "analytical fallback must not run when the measured model exists"
++        )
++
++        data_size_bytes = 2048 * 2048 * 2
++        expected_elements = data_size_bytes // 2
++        first = backend.predict_allreduce(data_size_bytes, num_devices=2)
++        second = backend.predict_allreduce(data_size_bytes, num_devices=2)
++
++        self.assertEqual(first, 0.321)
++        self.assertEqual(second, 0.321)
++        self.assertEqual(len(model.features), 1)
++        self.assertEqual(
++            int(model.features[0].iloc[0]["num_tokens"]), expected_elements
++        )
++        self.assertEqual(
++            backend._predictions["all_reduce"][(expected_elements,)], 0.321
++        )
++
++
++if __name__ == "__main__":
++    unittest.main()
diff --git a/runs/frontier-fidelity-envelope-v1/plot_mock_envelope.py b/runs/frontier-fidelity-envelope-v1/plot_mock_envelope.py
new file mode 100644
index 0000000..8d21765
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/plot_mock_envelope.py
@@ -0,0 +1,75 @@
+#!/usr/bin/env python3
+"""Render the preregistered fidelity-envelope figure prototype."""
+
+from pathlib import Path
+
+import matplotlib.pyplot as plt
+import numpy as np
+
+
+OUT = Path(__file__).with_name("mock-fidelity-envelope.png")
+
+
+def main() -> None:
+    workloads = ["F0\n2048/1", "F1\n512/1", "F2\n2048/128", "T1\nexact trace"]
+    variants = ["A0 analytical", "A1 native measured", "A2 measured+fix", "A3 +batch profile"]
+    # Prototype values are deliberately marked as MOCK and encode possible,
+    # distinguishable outcomes only. They are never read by result analysis.
+    regret = np.array(
+        [
+            [12.5, 14.0, 18.0, 25.0],
+            [11.0, 13.0, 16.0, 22.0],
+            [7.5, 10.0, 12.0, 18.0],
+            [2.0, 4.0, 7.0, 12.0],
+        ]
+    )
+
+    fig, (ax0, ax1) = plt.subplots(
+        1, 2, figsize=(11.5, 4.5), gridspec_kw={"width_ratios": [1.35, 1.0]}
+    )
+    x = np.arange(len(workloads))
+    width = 0.19
+    colors = ["#7f7f7f", "#4c78a8", "#f58518", "#54a24b"]
+    for index, (variant, color) in enumerate(zip(variants, colors)):
+        ax0.bar(
+            x + (index - 1.5) * width,
+            regret[index],
+            width,
+            label=variant,
+            color=color,
+        )
+    ax0.axhline(5.0, color="#d62728", linestyle="--", linewidth=1.5, label="5% gate")
+    ax0.set_xticks(x, workloads)
+    ax0.set_ylabel("Worst selected-config regret (%)")
+    ax0.set_title("A. Rank fidelity across workload complexity")
+    ax0.legend(fontsize=8, ncol=2, frameon=False)
+    ax0.grid(axis="y", alpha=0.25)
+
+    consumption = np.array(
+        [
+            [0, 0, 0],
+            [35, 65, 0],
+            [100, 0, 0],
+            [100, 0, 100],
+        ]
+    )
+    bottom = np.zeros(len(variants))
+    labels = ["measured collective hit", "analytical fallback", "batch-profile coverage"]
+    stack_colors = ["#4c78a8", "#e45756", "#54a24b"]
+    for values, label, color in zip(consumption.T, labels, stack_colors):
+        ax1.barh(variants, values, left=bottom, label=label, color=color)
+        bottom += values
+    ax1.set_xlim(0, 200)
+    ax1.set_xlabel("Coverage counters (normalized; separate axes by mechanism)")
+    ax1.set_title("B. Profile consumption, not just final rank")
+    ax1.grid(axis="x", alpha=0.25)
+    ax1.legend(fontsize=8, frameon=False, loc="lower right")
+
+    fig.suptitle("MOCK / preregistered layout — values are not experimental results", fontsize=12)
+    fig.tight_layout()
+    fig.savefig(OUT, dpi=180, bbox_inches="tight")
+    print(OUT)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/runs/frontier-fidelity-envelope-v1/profiles/measured-allreduce.csv b/runs/frontier-fidelity-envelope-v1/profiles/measured-allreduce.csv
new file mode 100644
index 0000000..85fedab
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/profiles/measured-allreduce.csv
@@ -0,0 +1,25 @@
+time_stats.all_reduce.min,time_stats.all_reduce.max,time_stats.all_reduce.mean,time_stats.all_reduce.median,time_stats.all_reduce.std,rank,num_workers,size,collective,devices_per_node,max_devices_per_node
+0.08288000151515007,0.08288000151515007,0.08288000151515007,0.08288000151515007,0.0,0,2,4096,all_reduce,2,8
+0.0793600007891655,0.0793600007891655,0.0793600007891655,0.0793600007891655,0.0,0,2,32768,all_reduce,2,8
+0.0713919997215271,0.0713919997215271,0.0713919997215271,0.0713919997215271,0.0,0,2,65536,all_reduce,2,8
+0.08056000247597694,0.08056000247597694,0.08056000247597694,0.08056000247597694,0.0,0,2,131072,all_reduce,2,8
+0.0865279994904995,0.0865279994904995,0.0865279994904995,0.0865279994904995,0.0,0,2,262144,all_reduce,2,8
+0.07135999947786331,0.07135999947786331,0.07135999947786331,0.07135999947786331,0.0,0,2,524288,all_reduce,2,8
+0.07321599870920181,0.07321599870920181,0.07321599870920181,0.07321599870920181,0.0,0,2,1048576,all_reduce,2,8
+0.09025600180029869,0.09025600180029869,0.09025600180029869,0.09025600180029869,0.0,0,2,2097152,all_reduce,2,8
+0.08083200082182884,0.08083200082182884,0.08083200082182884,0.08083200082182884,0.0,0,2,4194304,all_reduce,2,8
+0.10891199856996536,0.10891199856996536,0.10891199856996536,0.10891199856996536,0.0,0,2,8388608,all_reduce,2,8
+0.1703840047121048,0.1703840047121048,0.1703840047121048,0.1703840047121048,0.0,0,2,16777216,all_reduce,2,8
+0.25539200007915497,0.25539200007915497,0.25539200007915497,0.25539200007915497,0.0,0,2,33554432,all_reduce,2,8
+0.1021759994328022,0.1021759994328022,0.1021759994328022,0.1021759994328022,0.0,0,4,4096,all_reduce,4,8
+0.12694399803876877,0.12694399803876877,0.12694399803876877,0.12694399803876877,0.0,0,4,32768,all_reduce,4,8
+0.09161599725484848,0.09161599725484848,0.09161599725484848,0.09161599725484848,0.0,0,4,65536,all_reduce,4,8
+0.08580800145864487,0.08580800145864487,0.08580800145864487,0.08580800145864487,0.0,0,4,131072,all_reduce,4,8
+0.09867199882864952,0.09867199882864952,0.09867199882864952,0.09867199882864952,0.0,0,4,262144,all_reduce,4,8
+0.09646400064229965,0.09646400064229965,0.09646400064229965,0.09646400064229965,0.0,0,4,524288,all_reduce,4,8
+0.08377600088715553,0.08377600088715553,0.08377600088715553,0.08377600088715553,0.0,0,4,1048576,all_reduce,4,8
+0.1128000020980835,0.1128000020980835,0.1128000020980835,0.1128000020980835,0.0,0,4,2097152,all_reduce,4,8
+0.08755199983716011,0.08755199983716011,0.08755199983716011,0.08755199983716011,0.0,0,4,4194304,all_reduce,4,8
+0.12361599877476692,0.12361599877476692,0.12361599877476692,0.12361599877476692,0.0,0,4,8388608,all_reduce,4,8
+0.20030399411916733,0.20030399411916733,0.20030399411916733,0.20030399411916733,0.0,0,4,16777216,all_reduce,4,8
+0.2924960106611252,0.2924960106611252,0.2924960106611252,0.2924960106611252,0.0,0,4,33554432,all_reduce,4,8
diff --git a/runs/frontier-fidelity-envelope-v1/profiles/measured-allreduce.manifest.json b/runs/frontier-fidelity-envelope-v1/profiles/measured-allreduce.manifest.json
new file mode 100644
index 0000000..6ea2791
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/profiles/measured-allreduce.manifest.json
@@ -0,0 +1,15 @@
+{
+  "output": "/home/gahow/phd/aituner/runs/frontier-fidelity-envelope-v1/profiles/measured-allreduce.csv",
+  "output_sha256": "9d693fd406616b599e57bcde66c980c7fc2831b3acf37d3eb633cec80ea0070d",
+  "payload_contract": "size=num_tokens*hidden_dim*2_bytes",
+  "rows": 24,
+  "schema": "frontier-vidur-allreduce-materialization-v1",
+  "source": "/home/gahow/phd/aituner/runs/frontier-qwen30-vllm020-profile-v1/frozen/profile-v2/allreduce.json",
+  "source_sha256": "b38d14f990578d668523d25b107aceed433da5020d8ada3b6e44d3562261a3b3",
+  "target": "time_stats.all_reduce.median",
+  "tp_coverage": [
+    2,
+    4
+  ],
+  "unused_stat_policy": "repeat critical_path_median; std=0"
+}
diff --git a/runs/frontier-fidelity-envelope-v1/remote-sync-marker/README.md b/runs/frontier-fidelity-envelope-v1/remote-sync-marker/README.md
new file mode 100644
index 0000000..bf2fe4b
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/remote-sync-marker/README.md
@@ -0,0 +1,2 @@
+This directory is the gpu-fleet synchronization marker. Experiment code is
+synchronized to dash0 through the project Git branch before dispatch.
diff --git a/runs/frontier-fidelity-envelope-v1/run_flashattn_composition.sh b/runs/frontier-fidelity-envelope-v1/run_flashattn_composition.sh
new file mode 100644
index 0000000..03afe43
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/run_flashattn_composition.sh
@@ -0,0 +1,65 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+TP="${TP:?TP must be set to 1, 2, or 4}"
+case "${TP}" in
+  1|2|4) ;;
+  *) echo "ERROR: invalid TP=${TP}" >&2; exit 1 ;;
+esac
+
+OUTPUT_ROOT="${OUTPUT_ROOT:?OUTPUT_ROOT must be set}"
+VENV_ROOT="${VENV_ROOT:-/tmp/wjh/venvs/vllm-0.20.0-cu129-profiler-v1}"
+VLLM_SOURCE="${VLLM_SOURCE:-/home/admin/cpfs/wjh/agentic-kv/third_party/vllm_v20_build}"
+MODEL="${MODEL:-/home/admin/cpfs/wjh/models/Qwen/Qwen3-30B-A3B}"
+CAMPAIGN_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROFILE_SCRIPT="${CAMPAIGN_ROOT}/../frontier-qwen30-vllm020-profile-v1/profile_vllm020_flashattn.py"
+LOG_DIR="${OUTPUT_ROOT}/logs"
+PROVENANCE_DIR="${OUTPUT_ROOT}/provenance"
+BATCH_SPECS=(2q512 4q512 8q512 16q512 2q2k 4q2k)
+
+mkdir -p "${LOG_DIR}" "${PROVENANCE_DIR}" "${OUTPUT_ROOT}/raw"
+exec > >(tee -a "${LOG_DIR}/composition.log") 2>&1
+
+if [[ -z "${CUDA_VISIBLE_DEVICES:-}" ]]; then
+  echo "ERROR: CUDA_VISIBLE_DEVICES must contain the fleet-allocated GPU" >&2
+  exit 1
+fi
+IFS=',' read -r -a GPU_IDS <<< "${CUDA_VISIBLE_DEVICES}"
+if [[ "${#GPU_IDS[@]}" -ne 1 ]]; then
+  echo "ERROR: expected exactly one GPU, got ${CUDA_VISIBLE_DEVICES}" >&2
+  exit 1
+fi
+
+echo "PROFILE_LAUNCH_ECHO host=$(hostname) gpu=${CUDA_VISIBLE_DEVICES} model=${MODEL} runtime=vLLM-0.20.0+cu129 operator=FlashAttention3 tp=${TP} batch_specs=${BATCH_SPECS[*]} profile_script=${PROFILE_SCRIPT} output=${OUTPUT_ROOT} expected_wall=3-8m hard_wall=900s hard_gpu_cap=0.25_H20h"
+date -u +"START_UTC=%Y-%m-%dT%H:%M:%SZ"
+nvidia-smi --query-gpu=index,name,driver_version,memory.used,utilization.gpu --format=csv,noheader
+
+test -x "${VENV_ROOT}/bin/python"
+test -f "${VLLM_SOURCE}/benchmarks/attention_benchmarks/runner.py"
+test -f "${MODEL}/config.json"
+test -f "${PROFILE_SCRIPT}"
+
+git -C "${CAMPAIGN_ROOT}/../.." rev-parse HEAD > "${PROVENANCE_DIR}/aituner.commit"
+git -C "${VLLM_SOURCE}" rev-parse HEAD > "${PROVENANCE_DIR}/vllm-source.commit"
+sha256sum "${PROFILE_SCRIPT}" "${BASH_SOURCE[0]}" > "${PROVENANCE_DIR}/source.sha256"
+uv pip freeze --python "${VENV_ROOT}/bin/python" > "${PROVENANCE_DIR}/pip-freeze.txt"
+nvidia-smi --query-gpu=index,uuid,name,driver_version,memory.total --format=csv,noheader > "${PROVENANCE_DIR}/gpus.csv"
+printf '%s\n' "${BATCH_SPECS[@]}" > "${PROVENANCE_DIR}/batch-specs.txt"
+
+timeout --signal=TERM --kill-after=30s 780 \
+  "${VENV_ROOT}/bin/python" "${PROFILE_SCRIPT}" \
+  --vllm-source "${VLLM_SOURCE}" \
+  --model "${MODEL}" \
+  --output "${OUTPUT_ROOT}/raw/flashattn-composition-tp${TP}.json" \
+  --tp "${TP}" \
+  --batch-specs "${BATCH_SPECS[@]}" \
+  --warmup-iters 5 \
+  --repeats 10 \
+  --profile-kv-update
+
+test -s "${OUTPUT_ROOT}/raw/flashattn-composition-tp${TP}.json"
+sha256sum "${OUTPUT_ROOT}/raw/flashattn-composition-tp${TP}.json" "${PROVENANCE_DIR}"/* > "${OUTPUT_ROOT}/artifacts.sha256"
+nvidia-smi --query-gpu=index,name,memory.used,utilization.gpu --format=csv,noheader
+date -u +"END_UTC=%Y-%m-%dT%H:%M:%SZ"
+echo "FLASHATTN_COMPOSITION_COMPLETE tp=${TP} cases=${#BATCH_SPECS[@]}"
diff --git a/runs/frontier-fidelity-envelope-v1/smoke-report.md b/runs/frontier-fidelity-envelope-v1/smoke-report.md
new file mode 100644
index 0000000..f55c31b
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/smoke-report.md
@@ -0,0 +1,15 @@
+# Frontier measured-collective smoke
+
+日期：2026-07-17。设备：local CPU（Frontier simulation only）。Frontier commit：`d9cfeb6d8791fbf2f295dd9744c56a666171776e`，沿用既有 dirty compatibility patch set；A2 额外 patch SHA256 为 `35cc6be846589faf8cb5fa3ce5fdfe0aee8f086ba7dbb5dbcdc677148f19a3c8`。
+
+固定 cell：Qwen3-30B-A3B BF16 profile-v2，`TP2/MNS8/MBT8192`，`ISL=2048/OSL=1`，64 requests，8 req/s，prefix off，TTFT SLO 1256 ms。
+
+| variant | CC path for 2048-token payload | TTFT p50/p95/max (ms) | pass rate |
+|---|---|---:|---:|
+| A0 analytical | analytical | 122.2406276 | 1.0 |
+| A1 native Vidur | `4,194,304 > 100,000` elements，lookup miss 后 analytical fallback | 122.2406276 | 1.0 |
+| A2 measured + direct miss | measured random-forest estimator；exact payload memoized | 120.8898909 | 1.0 |
+
+A1 与 A0 的所有 TTFT 数值完全一致，验证 measured CSV 虽成功加载和训练，但没有参与该 payload 的 prediction。A2 model 对该 payload 的预测为 `0.09877793 ms`；同一个 TP2/2048 row 的 measured critical-path median 是 `0.10891200 ms`。A2 相对 A1 的 E2E delta 为 `-1.3507367 ms`（`-1.105%`），与每层多次 collective 的累计量级一致，因此通过“execution path 必须变化”的 smoke gate。
+
+这个 smoke 只证明 profile consumption；不证明 ranking 已恢复。下一步必须运行完整 A2 TP×MNS surface，并与已冻结 real capacity比较。
diff --git a/runs/frontier-fidelity-envelope-v1/test_fidelity_envelope.py b/runs/frontier-fidelity-envelope-v1/test_fidelity_envelope.py
new file mode 100644
index 0000000..3f5a79c
--- /dev/null
+++ b/runs/frontier-fidelity-envelope-v1/test_fidelity_envelope.py
@@ -0,0 +1,69 @@
+#!/usr/bin/env python3
+
+from __future__ import annotations
+
+import csv
+import importlib.util
+import json
+import sys
+import tempfile
+import unittest
+from pathlib import Path
+
+
+ROOT = Path(__file__).parent
+
+
+def load(name: str):
+    path = ROOT / name
+    spec = importlib.util.spec_from_file_location(path.stem, path)
+    assert spec and spec.loader
+    module = importlib.util.module_from_spec(spec)
+    sys.modules[spec.name] = module
+    spec.loader.exec_module(module)
+    return module
+
+
+class FidelityEnvelopeTest(unittest.TestCase):
+    def test_materialize_allreduce(self) -> None:
+        module = load("materialize_frontier_allreduce.py")
+        rows = []
+        for tp in (2, 4):
+            for tokens in (1, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192):
+                rows.append(
+                    {
+                        "tensor_parallel_size": tp,
+                        "num_tokens": tokens,
+                        "hidden_dim": 2048,
+                        "payload_bytes": tokens * 2048 * 2,
+                        "critical_path_median_ms": tp + tokens / 1000,
+                    }
+                )
+        with tempfile.TemporaryDirectory() as temporary:
+            root = Path(temporary)
+            source = root / "allreduce.json"
+            source.write_text(
+                json.dumps(
+                    {
+                        "schema_version": "qwen30_vllm020_allreduce_frozen.v1",
+                        "rows": rows,
+                    }
+                )
+            )
+            output = root / "all_reduce.csv"
+            manifest = module.convert(source, output)
+            self.assertEqual(manifest["rows"], 24)
+            with output.open(newline="") as handle:
+                converted = list(csv.DictReader(handle))
+            self.assertEqual(converted[0]["num_workers"], "2")
+            self.assertEqual(converted[0]["size"], "4096")
+            self.assertEqual(converted[-1]["num_workers"], "4")
+            self.assertEqual(converted[-1]["size"], str(8192 * 2048 * 2))
+            self.assertEqual(
+                converted[-1]["time_stats.all_reduce.median"],
+                str(4 + 8192 / 1000),
+            )
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/runs/frontier-phase-factorial-v0/run_frontier_qwen30_prefill_surface.py b/runs/frontier-phase-factorial-v0/run_frontier_qwen30_prefill_surface.py
index 10249d7..ecd0e74 100644
--- a/runs/frontier-phase-factorial-v0/run_frontier_qwen30_prefill_surface.py
+++ b/runs/frontier-phase-factorial-v0/run_frontier_qwen30_prefill_surface.py
@@ -48,6 +48,10 @@ def parse_args() -> argparse.Namespace:
     parser.add_argument("--requests", type=int, default=64)
     parser.add_argument("--rate", type=float, action="append")
     parser.add_argument("--config", action="append")
+    parser.add_argument(
+        "--cc-backend", choices=("analytical", "vidur"), default="analytical"
+    )
+    parser.add_argument("--allreduce-csv", type=Path)
     parser.add_argument("--timeout-seconds", type=float, default=900.0)
     parser.add_argument("--resume", action="store_true")
     return parser.parse_args()
@@ -182,6 +186,37 @@ def knobs(config: Config, paths: dict[str, Path], cache: Path) -> dict[str, Any]
     }
 
 
+def configure_cc_command(
+    command: list[str], *, backend: str, allreduce_csv: Path | None, cache: Path
+) -> list[str]:
+    configured = list(command)
+    option = "--cc_backend_config_type"
+    try:
+        index = configured.index(option)
+    except ValueError as error:
+        raise ValueError(f"Frontier command is missing {option}") from error
+    configured[index + 1] = backend
+    if backend == "analytical":
+        if allreduce_csv is not None:
+            raise ValueError("--allreduce-csv requires --cc-backend vidur")
+        return configured
+    if allreduce_csv is None:
+        raise ValueError("--cc-backend vidur requires --allreduce-csv")
+    configured.extend(
+        [
+            "--vidur_cc_backend_config_all_reduce_input_file",
+            str(allreduce_csv),
+            "--vidur_cc_backend_config_cache_dir",
+            str(cache),
+            "--vidur_cc_backend_config_k_fold_cv_splits",
+            "6",
+            "--vidur_cc_backend_config_num_training_job_threads",
+            "1",
+        ]
+    )
+    return configured
+
+
 def find_metrics(run_dir: Path) -> tuple[Path, Path]:
     systems = list((run_dir / "metrics").rglob("system_metrics.json"))
     requests = list((run_dir / "metrics").rglob("request_metrics.csv"))
@@ -231,6 +266,10 @@ def main() -> None:
     args.profile_root = args.profile_root.resolve()
     args.python_deps = args.python_deps.resolve()
     args.output_root = args.output_root.resolve()
+    if args.allreduce_csv is not None:
+        args.allreduce_csv = args.allreduce_csv.resolve()
+        if not args.allreduce_csv.is_file():
+            raise FileNotFoundError(args.allreduce_csv)
     rates = tuple(args.rate or RATES)
     selected = list(GRID)
     if args.config:
@@ -274,6 +313,12 @@ def main() -> None:
                 run_id=f"qwen30_prefill_{config.name}_r{rate:g}",
                 knobs=config_knobs,
             )
+            command = configure_cc_command(
+                command,
+                backend=args.cc_backend,
+                allreduce_csv=args.allreduce_csv,
+                cache=args.output_root / "cc-cache",
+            )
             write_json(run_dir / "command.json", command)
             environment = os.environ.copy()
             pythonpath = [str(args.python_deps), str(args.frontier_source)]
@@ -389,6 +434,15 @@ def main() -> None:
             "coverage": coverage,
             "sha256": {name: sha256(path) for name, path in paths.items()},
         },
+        "collective": {
+            "backend": args.cc_backend,
+            "allreduce_csv": (
+                str(args.allreduce_csv) if args.allreduce_csv is not None else None
+            ),
+            "allreduce_csv_sha256": (
+                sha256(args.allreduce_csv) if args.allreduce_csv is not None else None
+            ),
+        },
         "config_results": config_results,
         "capacity": capacities,
     }
diff --git a/runs/frontier-phase-factorial-v0/test_phase_factorial.py b/runs/frontier-phase-factorial-v0/test_phase_factorial.py
index 4172926..0ceb170 100644
--- a/runs/frontier-phase-factorial-v0/test_phase_factorial.py
+++ b/runs/frontier-phase-factorial-v0/test_phase_factorial.py
@@ -43,3 +43,20 @@ def test_kendall_tau_b() -> None:
     analysis = load("analyze_qwen30_prefill_fidelity.py")
     assert analysis.kendall_tau_b([1, 2, 3], [1, 2, 3])["kendall_tau_b"] == 1
     assert analysis.kendall_tau_b([1, 2, 3], [3, 2, 1])["kendall_tau_b"] == -1
+
+
+def test_configure_cc_command(tmp_path: Path) -> None:
+    surface = load("run_frontier_qwen30_prefill_surface.py")
+    base = ["python", "--cc_backend_config_type", "analytical", "--other", "x"]
+    analytical = surface.configure_cc_command(
+        base, backend="analytical", allreduce_csv=None, cache=tmp_path
+    )
+    assert analytical == base
+    profile = tmp_path / "all_reduce.csv"
+    profile.write_text("header\n")
+    vidur = surface.configure_cc_command(
+        base, backend="vidur", allreduce_csv=profile, cache=tmp_path / "cache"
+    )
+    assert vidur[2] == "vidur"
+    assert "--vidur_cc_backend_config_all_reduce_input_file" in vidur
+    assert str(profile) in vidur
diff --git a/runs/frontier-qwen30-vllm020-profile-v1/freeze_frontier_profiles.py b/runs/frontier-qwen30-vllm020-profile-v1/freeze_frontier_profiles.py
index 0d420e0..16f1b68 100644
--- a/runs/frontier-qwen30-vllm020-profile-v1/freeze_frontier_profiles.py
+++ b/runs/frontier-qwen30-vllm020-profile-v1/freeze_frontier_profiles.py
@@ -114,7 +114,7 @@ MOE_METADATA = (
 def parse_args() -> argparse.Namespace:
     parser = argparse.ArgumentParser()
     parser.add_argument("--linear", type=Path, required=True)
-    parser.add_argument("--attention", type=Path, nargs=3, required=True)
+    parser.add_argument("--attention", type=Path, nargs="+", required=True)
     parser.add_argument("--moe", type=Path, required=True)
     parser.add_argument("--router", type=Path, required=True)
     parser.add_argument("--allreduce", type=Path, nargs=2, required=True)